Abstract: In the diagnostic method for detecting erroneous operation of a knock sensor of an internal combustion engine an actual reference level is formed from knock sensor signals generated by the knock sensor; then two minimum knock detection thresholds consisting of rotation speed values are defined and compared with rotation speed to test whether or not rotation speed exceeds each minimum knock detection threshold; the reference level is then compared with at least one of an upper reference level threshold and a lower reference level threshold, but only with the upper reference level threshold when a lower minimum knock detection threshold is exceeded, and a diagnostic signal indicative of a knock sensor fault or error is generated when the reference level exceeds the upper reference level threshold or falls below the lower reference level threshold, if and only if engine rotation speed exceeds at least one of the minimum knock detection thresholds.

Abstract: A method for knock control during KC emergency operation with which, given low application expenditure, a torque gain can be attained, while the application reliability increases. The method for knock control of multi-cylinder internal combustion engines having 2n cylinders, a cylinder counter, at least one knock sensor and an evaluation unit for evaluating the knock-sensor signal with the aid of an individual knock-recognition characteristic for each cylinder, is characterized in that during KC emergency operation, cylinder pairs are formed from the cylinders operating offset in each case by 360°, and the minimal value of the two knock-recognition characteristics of the cylinder pair is assumed in each case as the knock-recognition threshold for the cylinders of the cylinder pair affected by the malfunction of the phase recognition.

Abstract: The method and the device are used for cylinder shut-off in an internal combustion engine (10), in particular of a vehicle, using a control unit (15) in effective operational contact with the cylinders (11, 12, 13, 14) of the internal combustion engine (10), which has a monitoring unit (21), a knock regulating unit (20) and a fuel injector shut-off unit (22). At the same time the provision is made that the fuel injector shut-off unit (22) is operationally linked to the knock regulating unit (20) to achieve coordinated cylinder shut-off. The fuel injector shut-off unit (22) is provided with a memory medium (23) for storing a cylinder shut-off program.

Abstract: The apparatus detects knock in an internal combustion engine with at least one knock sensor associated with a cylinder of the internal combustion engine. The apparatus initially processes the analog knock sensor output signals in an analog signal preparing device (18), which can include a multiplexer and analog/digital converter, but the actual knock detection occurs only in a purely digital signal analysis device (19), which processes the prepared and digitized knock sensor output signals. The digital signal analysis device (19) extracts at least one knock index and compares it with predetermined threshold values for knock detection, preferably considering a reference value for knock-free operation. A method of detecting knock is also described which is based on the use of this apparatus.

Abstract: A method and a corresponding apparatus for operating an internal combustion engine are proposed, in which in at least one cylinder, combustion of a fuel in a fuel/air mixture introduced into the cylinder takes place. Upon the occurrence of knocking, a baseline ignition angle in the at least one cylinder is retarded in steps, using a knock control system, to an adjustment angle from the basic ignition angle. When the adjustment angle exceeds a definable threshold value, activation of the knock prevention operation mode occurs, in which context an additional action reducing the knock susceptibility of the fuel/air mixture is taken and the adjustment angle is decreased so that the baseline ignition angle is advanced.

Abstract: A device for suppressing engine knocks in an internal combustion engine, using a detection device for the detection of the respective operating parameters of the internal combustion engine; a control unit for determining manipulated variables for the injection and ignition on the basis of the acquired operating parameters; a dynamic phase detection device for acquiring a dynamic phase of the internal combustion engine; and a correction device for correcting the manipulated variables for the ignition, which is constructed so that for knock suppression, the ignition control quantity, given a dynamic phase acquired by the dynamic phase detection device, can be adjusted in the late direction by a dynamic lead that is dependent on a predicted load difference, and at the end of the dynamic phase can be brought step-by-step back to the manipulated variable determined by the control unit.

Abstract: A method and a device for fault detection or diagnosis are described which are used on a multi-cylinder internal combustion engine with a knock sensor. For diagnostic purposes an instantaneous reference value formed from the sensor signal is compared with predefinable upper or lower reference threshold levels. If the instantaneous reference value exceeds or falls below the thresholds to a predefinable extent, a malfunction is detected. The reference levels correspond, for example, to the background noise present in knock-free operation. The fault detection or diagnosis is performed only for the cylinder which emits the loudest noise or from which the loudest noise is recorded.

Abstract: A method for knock control during KC emergency operation with which, given low application expenditure, a torque gain can be attained, while the application reliability increases. The method for knock control of multi-cylinder internal combustion engines having 2n cylinders, a cylinder counter, at least one knock sensor and an evaluation unit for evaluating the knock-sensor signal with the aid of an individual knock-recognition characteristic for each cylinder, is characterized in that during KC emergency operation, cylinder pairs are formed from the cylinders operating offset in each case by 360°, and the minimal value of the two knock-recognition characteristics of the cylinder pair is assumed in each case as the knock-recognition threshold for the cylinders of the cylinder pair affected by the malfunction of the phase recognition.

Abstract: The diagnostic process for use in evaluation of sensor signals, especially in evaluation of the output signals of a knock sensor in an internal combustion engine, includes determination of a reference level from the amplified sensor signal, which is compared with a predetermined lower and/or upper limiting value for error detection. An error is detected as a predetermined variation of the reference level from the limiting values. At least one of the limiting values is doubled and selection of the one or the other of the doubled threshold values occurs with the aid of predetermined conditions, e.g. of the internal combustion engine.

Abstract: The method for knock detection includes establishing that knock is occurring in the internal combustion engine when the amplified knock signal exceeds a predetermined reference level in a predetermined manner. The reference level is determined on the basis of individual cylinders and the increase in the reference level is limited when a new reference level leaves a predetermined reference level range or the gradient of the sound increase exceeds a predetermined threshold value. For determination of the reference level range and/or the threshold for the gradient average values of the signals originating from the sound of other cylinders are considered.

Abstract: The apparatus detects knock in an internal combustion engine with at least one knock sensor associated with a cylinder of the internal combustion engine. The apparatus initially processes the analog knock sensor output signals in an analog signal preparing device (18), which can include a multiplexer and analog/digital converter, but the actual knock detection occurs only in a purely digital signal analysis device (19), which processes the prepared and digitized knock sensor output signals. The digital signal analysis device (19) extracts at least one knock index and compares it with predetermined threshold values for knock detection, preferably considering a reference value for knock-free operation. A method of detecting knock is also described which is based on the use of this apparatus.